Process of manufacturing alloys of aluminium



PATENT OFFICE.

JOHN W. LANGLEY, OF EDGEWOODVILLE, ASSIGNOR OF ONE-I-IAIJF TO HUNT (KiOLAPP, OF PIT'I SBURG, PENNSYLVANIA.

PROCESS OFIMANUFACTURING ALLOYS OF ALUMINIUM.

I SPECIFICATION formingpart of Letters Patent No. 451,404, dated April28, 1891.

Application filed September 20, 1890- Serial No. 36b,657. (Nospecimens.)

and State of Pennsylvania, have invented a new and useful Improvement inProcesses of ManufacturingAlloys of Aluminium, of which .the' followingis a full, clear, and exact de scription. I

My invention has for its object to provide means whereby aluminium canbe alloyed economically with such metals as'titanium',tung- 'sten,boron, chromium, &c;, which are difficult and costly to obtain in ametallic state.

I have discovered that of such metals the metal tita-v nium especiallyproduces definitely beneficial results when alloyed with aluminium andimproves the properties of the latter in many Thus I have found thatwhentitanium it produces a metal which is of low specific gravity andeasily malleable, but is .intrinsi:

cally harder than pure aluminium, and is adapted to acquire, byhammering or rolling, a degree of elasticity comparable to that ofspring-brass. -The obviously undue-cost of alloying suclr rare metals astitanium, &c., with aluminium by simple fusion of the metallic elementshas led to attempts to make the alloy by the reduction of their oxidesin the presence of aluminium; but'hithertosuch attempts have not risenabove the category of mereu-nsatisfactory laboratory experiments,

7 and have not demonstrated the feasibility of I producing such alloyasja useful article of commerce. I have succeeded in solving the prob.-.lem thus presented, and for the first time have made it possible toproduce a useful alloy of ftneifinn above descri an; acheap and readymanner.

shall explain the application-of my invention In the course of thefollowing descriptionI to the alloying of 'alujiin'ium'wit-htitanium,since it is this alloy thatI deem to be the most useful, Premi'sing,however, that by substitutlog for the titanic oxide ori salt the. oxidesor salts of other metals more electro-negative.

than aluminium the metallic bases of such oxides or'salts may be alloyedwith aluminium in like manner. Metals which can be alloyed thus withaluminium are bismuth. cadmium,

fluoride of sodium, or of fluorides of alumirp ium, sodium, and calcium,or, generally, a fluoride or fluorides of a metal or metals moree1ectro-positive than aluminium. I may add to these fluorides chloridesof the alkalies or alkaline earths; but these are unnecessary. Cryoliteof commerce may be used as the fluoride constituentof the bath; but,although I do not exclude its use from the scope of the broad claim ofthis application, it is in some respectsdisadvantageous because of itsiron, which in the alloying process hereinafter de-' scribed is reduced,and bymingling with the alloy impairs its quality. For this reason I-'prefer to employ the above-mentioned fluoride in as pure state aspossible. fore or after the fusion of this fluoride bath 1 add to it areducible oxide or saltof the rare metal to be alloyed. In making analloy of aluminium and titanium titanic oxide is pref Either beerablyused, and after thoroughadmixture ofthese substances, the oxide or saltbeing dissolved by the fluoride, I introducethe aluminium, whichmay lieintroduced eitherjn amolten state or in asolid state. Whenintroduced insolid state, it is fused by the heat of the bath, and whenfused areaction between the aluminium and said oxide or salt at once takesp1aces,'the oxide or salt is reduced, its

oxygen or acid radical combines with apart of the aluminum, and thefreedmetallic base immediately alloys with the remainder of the aluminium. Inpractice I prefer tozuse as the ranging from one hundred .to fourhundred per: cent. of the weight of the aluminium intended to be added.This bath I melt in a carbon crucible, and add thereto the oxide or'fiuoride'bath fluorides of' aluminium and so: 'dinm, which may beemployed in amount salt of the metal to be alloyed. When the whole mass-is incorporated and as nearly fluid as possiblalchargemetallicaluminium into the'erucible, the relative proportions: of.

the aluminium and oxide or salt being such that the percentage of oxideor salt shall be 1 about twice the percentage in which its metallic baseis desired to be present in the alloy. Immediately on the introductionof the aluminium the reaction above noted takes place between thealuminium and the oxide or salt and is'accompanied by a rapid elevationof temperature of the bath. After waiting until further reaction ceases,which is indicated by cessation of rise of the temperature, the contentsof the crucible are poured into a suitable receptacle, and after coolingsomewhat the melted fluoride can be separated as a supernatant slag fromthe metallic alloy at the bottom of the vessel. is then collected, andis preferably remelted to cleanse it thoroughly from slag and otherwiseto improve-its properties. a

It is important that the reduction of the oxide or salt of titanium andits alloying with the aluminium should be conducted in a nonsiliciouscrucible, (preferably a carbon crucible,) since it the vessel besilicious in its composition a considerable portion of silicon will bealloyed with the aluminiumand titanium, producing a compound of inferiorquality.

. In the foregoing specification I have recited particularly the orderin which I preferto conduct the steps of my process, and as this Thealloy succession of steps enables me to obtain uniformity and certaintyin the product by making it easier to regulate the react-ionsI intend toclaim it specifically, but do not limit thereto those claims in whichsuch order is not expressed.

I claim 1. In the art of alloying aluminium with more electro-negativemetals whose oxides or -salts are difiicult of reduction, the methodbase of the oxideor salt is reduced and alloyed, substantially asdescribed.

In testimony whereof I have hereunto set my hand this 18th day ofSeptember, A. D. 1890.

- "JOHN W. LANGLEY.

" Witnesses:

THOMAS W. BAKEWELL,

W. 13.. CORWIN.

